This invention relates generally to apparatus for application of therapeutic electro-massage and more particularly to an electrode glove for use by a therapist to effectively apply a combination of whole hand massage and electrical stimulation to a patient.
Transcutaneous electrical nerve stimulation (TENS) involves the delivery of electrical energy through human skin tissue to excite underlying nerves. It is known that the selective stimulation of the large, myelinated afferent nerve fibers in a painful area can reduce pain by altering the pattern of neural inputs to the spinal cord. It has also been suggested that TENS may provide pain relief by inducing the release of natural pain killers such as beta-endorphin. TENS is applied through electrodes which are affixed to the patient's skin. Although TENS has been used mainly to stimulate nerve fibers to relieve pain, it can also be use to elicit muscle contractions if sufficient energy is applied. Attempts have been made to combine the beneficial effects of transferring electrical energy to human tissue together with manual massage. However, known devices for such use leave much to be desired for performing electro-massage on the deep muscles of the neck, shoulders, or back.
When massaging the lower back, the therapist is required to apply pressure with the thenar and hypothenar eminence, commonly called the heel of the hand, together with the fleshy prominences covering the palmar surface of the metacarpal-phalangeal articulations, i.e. the palm-side of the knuckle joints. Accordingly, electrodes must be disposed on these surfaces to obtain effective electro-massage. Known devices for electro-massage such as those described in Brenman, U.S. Pat. No. 4,510,939; Shepard, U.S. Pat. No. 3,556,105; and Fournier, French Patent No. 967,374 have very small electrodes disposed on particular parts of the respective glove or mitten, such as the tips of specific fingers. The electrodes used for these devices are effectively point electrodes. Such small electrodes are undesirable for use with TENS because the high current densities resulting therefrom can cause burning of the skin tissue.
Furthermore, the above noted devices have the anode and cathode in close proximity. Such close proximity between the anode and cathode reduces the depth of current penetration in biological tissue. Additionally, there is a greater risk of shorting between the anode and cathode during hand movement.
Other gloves for electro-massage therapy have been devised with larger surface electrodes. However, all of these also have disadvantages. For example, an electrotherapeutic glove described in Elmvall, U.S. Pat. No. 1,545,413, has a plurality of small metallic electrodes wired together in a mesh which covers the palmar surface of the glove. The use of metallic electrodes directly on the skin, however, is undesirable because metallic ions may pass into the body with electric current. Also, the high resistance of the skin tends to convert electric energy into heat when bare metal makes contact with the skin, resulting in burning. Schnee U.S. Pat. No. 1,536,273, describes a mitten for therapeutic massage in which a conducting mesh is covered with a moisture absorbing fabric. Morell, U.S. Pat. No. 206,474, describes an electrode glove in which the metallic electrode is covered with sponge material. Such devices must be taken out of service to be washed after a single use. In the case of sponge material, the device cannot be easily cleaned at all and has a short life expectancy when repeatedly rubbed on the skin as is required in massage therapy.
Other types of electrode gloves such as described in Lewin, U.S. Pat. No. 401,041, and French Patent No. 446,865 have one or more wires disposed along the palmar surface of the glove which are covered with a moisture absorbing fabric such as cloth or leather. In addition to the problems of keeping such devices clean after use, the wire electrodes may break with repeated use and can pierce the fabric causing pain and possible injury to the patient.
All of the electrode gloves described above are difficult to fabricate because they include a combination of insulating materials, metallic conductors, and moisture absorbing fabrics. These varied materials are not easily assembled together and special manufacturing and assembling techniques are required.